drm/vboxvideo: Run DRM default client setup

Call drm_client_setup() to run the kernel's default client setup
for DRM. Set fbdev_probe in struct drm_driver, so that the client
setup can start the common fbdev client.

The vboxvideo driver specifies a preferred color mode of 32. As this
is the default if no format has been given, leave it out entirely.

v5:
- select DRM_CLIENT_SELECTION

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Hans de Goede <hdegoede@redhat.com>
Acked-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240924071734.98201-71-tzimmermann@suse.de

Author: tdz

drivers/gpu/drm/vboxvideo/Kconfig

@@ -2,6 +2,7 @@
 config DRM_VBOXVIDEO
 	tristate "Virtual Box Graphics Card"
 	depends on DRM && X86 && PCI
+	select DRM_CLIENT_SELECTION
 	select DRM_KMS_HELPER
 	select DRM_VRAM_HELPER
 	select DRM_TTM

drivers/gpu/drm/vboxvideo/vbox_drv.c

@@ -13,6 +13,7 @@
 
 #include <drm/drm_aperture.h>
 #include <drm/drm_atomic_helper.h>
+#include <drm/drm_client_setup.h>
 #include <drm/drm_drv.h>
 #include <drm/drm_fbdev_ttm.h>
 #include <drm/drm_file.h>
@@ -80,7 +81,7 @@ static int vbox_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (ret)
 		goto err_irq_fini;
 
-	drm_fbdev_ttm_setup(&vbox->ddev, 32);
+	drm_client_setup(&vbox->ddev, NULL);
 
 	return 0;
 
@@ -193,6 +194,7 @@ static const struct drm_driver driver = {
 	.patchlevel = DRIVER_PATCHLEVEL,
 
 	DRM_GEM_VRAM_DRIVER,
+	DRM_FBDEV_TTM_DRIVER_OPS,
 };
 
 drm_module_pci_driver_if_modeset(vbox_pci_driver, vbox_modeset);